The invention relates to a trailer coupling comprising a cross member which is mountable on a rear region of a vehicle body, a pivot bearing unit arranged on the cross member, by means of which a ball neck carrying a coupling ball is pivotally mounted about a pivot axis between a working position and a rest position, and a contact unit, in particular a plug connection unit, arranged on the ball neck for establishing an electrical plug connection to produce an electrical connection to a unit which is fixable on the ball neck, in particular to a plug of this unit, and comprising a cable harness guided from the contact unit to a vehicle-mounted cross member and provided for connecting to a vehicle electrical supply system.
Trailer couplings of this type are known from the prior art, but these have the problem of guiding the cable harness from the ball neck to a vehicle connection in a suitable manner.